Influence of mechanical reinforcement of MgB2 wires on the superconducting properties

Monofilamentary MgB2-wires with a mechanical tough Nb/Cu/steel or Fe/steel sheath were prepared and characterized. The steel content was varied to investigate the reinforcement effect and the consequences for the superconducting properties of the wires, which were heat treated to achieve dense and homogeneous filaments. The use of Nb as first sheath layer, having a smaller thermal expansion coefficient than MgB2, requires the application of higher amounts of steel to achieve compressive pre-stress on the filament in comparison to Fe as first wall material. With raised steel content in the sheath the critical transport currents show field dependent significant critical current and irreversibility field degradations. First Ic vs. axial stress and strain experiments confirmed this observation of pre-stress induced degradations. Consequences for improved wires and for future applications will be discussed.Comment: 14 pages, 7 figures, 1 table; Submitted to Physica C; presentation at ISS-2001, Kobe Japa

Patient Perceptions of Bedpan Usage and Comfort Levels

While it may be seemingly obvious, there is very little data on patient perceptions of bedpan use. In order to create a better bedpan, there needs to be evidence as to why it is necessary. The objective of this study is to explore patient experiences of bedpan use in order to define their perceptions of comfort levels. The literature shows that patients are physically and emotionally uncomfortable when using the bedpan, find the device unpleasant, and are not receiving the necessary levels of education and compassion from their care staff. A mixed methods study using a descriptive quantitative design was developed to further explore the patient experience of using a bedpan. A convenience sample of 50 participants in acute and long term care settings completed an interview tool developed by the researchers. Descriptive statistics were used to analyze frequencies and Chi square analysis was used to define statistically significant relationships. Patients identified major problems with physical, psychosocial, sociocultural, and environmental aspects of bedpan us, with frequent report of discomfort, embarrassment, improper positioning, and adverse device characteristics. Patients are experiencing unnecessary pain and are at risk for infection and constipation due to discomfort and embarrassment. Redesigning the bedpan will be integral to improving patient experiences

Analysis of Petri Nets and Transition Systems

This paper describes a stand-alone, no-frills tool supporting the analysis of (labelled) place/transition Petri nets and the synthesis of labelled transition systems into Petri nets. It is implemented as a collection of independent, dedicated algorithms which have been designed to operate modularly, portably, extensibly, and efficiently.Comment: In Proceedings ICE 2015, arXiv:1508.0459

Accelerating Eulerian Fluid Simulation With Convolutional Networks

Efficient simulation of the Navier-Stokes equations for fluid flow is a long standing problem in applied mathematics, for which state-of-the-art methods require large compute resources. In this work, we propose a data-driven approach that leverages the approximation power of deep-learning with the precision of standard solvers to obtain fast and highly realistic simulations. Our method solves the incompressible Euler equations using the standard operator splitting method, in which a large sparse linear system with many free parameters must be solved. We use a Convolutional Network with a highly tailored architecture, trained using a novel unsupervised learning framework to solve the linear system. We present real-time 2D and 3D simulations that outperform recently proposed data-driven methods; the obtained results are realistic and show good generalization properties.Comment: Significant revisio

Structural and Functional Studies of Proteins from the Agricultural Pests Tetranychus Urticae and Aspergillus Fumigatus

Agricultural pests are a worldwide problem and cause billions of dollars in crop loss. In the United States alone, an estimated $40 billion USD is lost per year due to insecticide resistance [1]. Studied here are proteins (potentially new pesticide targets) from the agricultural pests Tetranychus urticae and Aspergillus fumigatus. T. urticae, or twospotted spidermite, is a polyphagous pest, and three proteins from this pest, a cyanase, a glutathione S-transferase and an intradiol ring-cleavage dioxygenase are described [2]. Cyanase is involved in the conversion of bicarbonate and cyanate, a toxic self-defense metabolite produced by plants, into ammonia and carbon dioxide. Glutathione Stransferase conjugates reduced glutathione to xenobiotics for detoxification and have been associated with insecticide resistance [3]. Intradiol ring-cleavage dioxygenase is involved in the breakdown and metabolism of toxic aromatic compounds. Furthermore, A. fumigatus is a ubiquitous fungus that is not only a problem in agriculture, but also in healthcare. A. fumigatus drug resistance is becoming more prominent which is mainly attributed to the widespread use of fungicides in agriculture [4]. The 2-methylcitrate cycle, which is only present in fungi, is responsible for detoxifying propionyl-CoA, a toxic metabolite produced as the fungus breaks down proteins [5]. The enzyme responsible for this detoxification is 2-methylcitrate synthase (mcsA) and is a potential candidate for the design of new anti-fungals. However, mcsA shares a similar reaction to human citrate synthase (hCS), and both the structure and function of each enzyme is studied in parallel to find mcsA-specific inhibitors

Bounded Petri Net Synthesis from Modal Transition Systems is Undecidable

In this paper, the synthesis of bounded Petri nets from deterministic modal transition systems is shown to be undecidable. The proof is built from three components. First, it is shown that the problem of synthesising bounded Petri nets satisfying a given formula of the conjunctive nu-calculus (a suitable fragment of the mu-calculus) is undecidable. Then, an equivalence between deterministic modal transition systems and a language-based formalism called modal specifications is developed. Finally, the claim follows from a known equivalence between the conjunctive nu-calculus and modal specifications